-LRB- CNN -RRB- -- Brian McLaughlin used to arrive 20 minutes early to on-site client meetings . He would drive around the parking lot to find a space close to the building , and then go inside to cool off from the short walk . The extra weight he was carrying made him sweat constantly inside his suit .

McLaughlin had struggled with weight his entire life . At age 10 he weighed 140 pounds ; at age 20 he was 280 pounds . By 30 , he had reached his heaviest weight of 330 pounds .

In 2010 , McLaughlin moved from Ireland to New York , after landing a job as software architect for the New York Stock Exchange . He went out for lunch and dinner with his new American co-workers in an attempt to socialize and make friends -- sacrificing all hopes of eating healthy .

`` I was living a bachelor lifestyle , '' says McLaughlin . `` I would eat and drink a lot , which played havoc with the weight . ''

He tried The Atkins Diet and Weight Watchers but nothing seemed to click .

He watched as his mother lost 50 pounds on a diet program called Slimming World , which advocates dieting without deprivation of the foods you like . And he saw his girlfriend shed 100 pounds on Weight Watchers .

Seeing living proof that people can lose weight inspired him to make some changes of his own .

A social sacrifice

It was tough to stop going out to eat for lunch and dinner , McLaughlin says . He used to go out with his co-worker a couple of times a week and indulge in a half-dozen strong cocktails before -LRB- and after -RRB- lavish three-course meals .

`` I 'd usually have an appetizer of cured meats , the largest available steak , or a rack of lamb for mains , a side of vegetables sautÃ © ed in butter or oil , rich desserts like molten chocolate lava cake or chocolate ganache and a cheese board with dessert wine to finish , '' says McLaughlin .

Between the two of them , McLaughlin says they would split three bottles of wine with dinner .

`` I ca n't remember a meal where I walked away not feeling completely stuffed to the point of almost being sick , '' he says . `` Dinner and drinks used to add up to 5,000 calories alone . ''

Now he follows the Slimming World plan and prepares his meals at home . They usually consist of fruit and either chicken rubbed with dry spices , or fillet and broccoli or cauliflower . When he does eat out , he chooses carefully .

`` I love the dining experience and social aspect , '' says McLaughlin . `` But I realize a 6 - or 8-ounce filet is more than enough now . ''

He also tries to skip cocktail hour .

`` Now I tend to drink wine only , and I enjoy and savor the taste instead of just drinking for the sake and experience , '' McLaughlin says .

Different diet , same result

McLaughlin 's girlfriend , Allison Dressler , says she found it hard to cook in the beginning of their relationship due to their different diet meal plans .

She followed Weight Watchers , which focuses on a point system to limit calories . For Slimming World , McLaughlin would worry about every drop of oil , butter or cooking spray because those were restricted under the diet plan .

`` As we cooked more and more we realized a lot of the things he eats are actually good for me , '' says Dressler . `` And a lot of things I eat are n't that bad for him , either . ''

Neither Dressler nor McLaughlin have gym memberships ; they simply walk a few miles a couple of days of the week . McLaughlin did n't want to drastically change his workout plan because he feared he would n't be able to stay motivated .

`` It 's hard to go to the gym after work , '' he says . `` I really wanted to focus on controlling my eating habits more than anything . ''

That strategy worked . In the last three years , McLaughlin has lost 140 pounds .

McLaughlin now goes to work more than two hours earlier than he used to and finishes earlier , which has increased his productivity .

`` I do n't feel that constant sluggish feeling anymore , '' he says .

His energy has also increased dramatically ; he no longer lies in bed watching The Food Network until the afternoon .

When he first moved to New York , his only hobby was eating and drinking -- now he spends his weekends researching farmers markets to visit , chili festivals , wine stores and fruit-picking spots .

The couple recently went on vacation and chose to walk to their terminal rather than take the moving pavements like they use to .

Dressler says its these small changes that make the biggest differences .

`` A lot of my life still revolves around food and drink , but it 's no longer destructive , '' says McLaughlin .

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McLaughlin has struggled with weight his entire life

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After seeing family members ' weight loss , he tried a program called Slimming World

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He has lost about 140 pounds in three years

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McLaughlin says his weight loss has improved his career and made him more productive